The 95-year-old visited the monument in London’s Green Park in 2013 and said he was inspired to make the sacrifice “out of comradeship” to his fellow servicemen who did not made it back.
Sq Ldr Munro said it was important for the memorial to maintain its condition for the relatives of the thousands of men listed on it and future generations.
The monument was built 67 years after the end of the war to commemorate the RAF aircrew and groundstaff from Britain and Commonwealth countries who died on bombing operations in the war.
The charity, the RAF Benevolent Fund, has the duty to pay for its maintenance and upkeep at a cost of £50,000 a year.
Out of the 19 commanding officers who flew on the famous 1943 raid to destroy three dams in Germany’s industrial heartland, Sq Ldr Munro is the last one alive today.
Eight them were killed during the mission, making up the total of 53 out of 133 crew killed.
Despite the losses, the raid – codenamed Operation Chastise – was a success with two dams breached by Dr Barnes Wallis’ ingenious bouncing bombs, wiping out scores of armament factories in the Ruhr Valley.
Sq Ldr Munro’s Lancaster bomber was struck by an anti-aircraft flak shell on the raid over Holland, knocking a gaping hole in the fuselage and putting all communications out of use, forcing the crew to turn back still carrying its mine.
He was awarded the Distinguished Service Order for the raid. Sq Ldr Guy Gibson, who led the mission, received the Victoria Cross.
Sq Ldr Munro was also awarded the Distinguished Flying Cross for bravery shown during 58 sorties over Europe.
Squadron Leader Les Munro in the cockpit of a Lancaster (BNPS)
Serving with 97 and then 617 Squadron, he bombed German aircraft and armament factories, V1, V2 and V3 rocket sites, E and U-Boats pens and tunnels all over Europe.
On the eve of D Day in 1944, he dropped aluminium strips in the English Channel to trick German radar operators into thinking the invasion was taking place at Calais rather than Normandy to the south.
The £50,000 expected from the sale of his medals and log books will be enough to pay for the maintenance of the memorial for a whole year.
Sq Ldr Munro, from New Zealand, said: “The memorial is a magnificent tribute to Bomber Command’s fallen. It was a travesty it took 67 years before the loss of 55,573 lives was finally recognised.
“My reasons for donating my medals and flying log books to the fund were prompted by my visit. I could not help but think of the cost of its ongoing maintenance and with the feelings of the descendants of those 55,573 in mind believe that every effort be made to maintain the memorial in the best possible condition.
Squadron Leader Munro’s medals (BNPS)
He added: “My war service moulded me as a man; it gave me the confidence in my own ability and taught me to get on with my fellow men and value comradeship.
“It is because of that sense of comradeship and the equal importance of the act of remembrance that I now part company with my medals for the benefit of the Bomber Command Memorial.”
Mike Neville, director of strategy and fundraising at the RAF Benevolent Fund, said: “We are enormously grateful to Les for his donation. It was very much his decision and he approached us with it.
“Les will consider it a small sacrifice compared to the sacrifice made by thousands of his comrades in the war but to us it really is a big one because the proceeds of the sale should pay for a whole year’s maintenance.”
The medals, which also include the New Zealand Order of Merit, are to be sold by London auctioneers Dix Noonan Webb.
Christopher Hill, a director at the auction house, said: “Les Munro is a remarkable man whose spirit of adventure has never left him.
“It is entirely typical of him that he is selling his medals, log books and other memorabilia to help ensure that the memory of his dead comrades will never fade.”
Les Munro (centre front) with crew before flying on Dambusters raid (Dix Noonan Webb/BNPS)
Sq Ldr Munro’s father was Scottish and emigrated to New Zealand in 1903 and became a shepherd. He joined the Royal New Zealand Air Force in 1941 and arrived in Britain the following year, flying with the 97 Squadron.
He was the captain for bombing raids on aircraft and armament factories in Berlin, Essen, Dusseldorf, Cologne, Hamburg, Stuttgart, Milan and Turin.
In 1943, he volunteered for the 617 “Dambusters” Squadron and was reportedly chosen by Guy Gibson to take part in the dams raid.
Sq Ldr Munro learned to fly Lancaster bombers at below tree-top height at 200mph in preparation for the raid.
On one such flight over Lincolnshire, he was nearly killed when a seagull hit his cockpit windscreen “like a cannonball” and landed between him and his co-pilot.
He went on to practice for the mission over Derwent Water in the Lake District and the Fleet at Chesil Beach.
Two days after the Allied invasion of Europe, Sq Ldr Munro dropped the first “Tallboy” 12,000lbs bomb on a tunnel in southern France that enemy Panzer tanks were using to reinforce Germany army in Normandy.
The RAF’s Dambusters squadron in action during the Second World War
He then led successful raids to wipe out E-boat and U-boat pens in Le Havre and Boulogne, successful missions that helped the Allied take control of Normandy and France.
After the war he returned to New Zealand, studied agriculture and worked for the State Advances Corporation which managed state-owned farms.
He got into local politics and served as mayor of Waitomo, a town on the northern island of New Zealand. He was appointed to the Queen’s Service Order (Q.S.O.) in 1991.
The men of Bomber Command suffered huge losses in the Second World War, with 45 out of every 100 airmen killed.
A permanent memorial for Bomber Command was not built for 67 years due to the controversy of thousands of German civilians who died during the bombings of its cities.
Painting of Lancaster bombers from the RAF’s No 617 Squadron attacking Moehne dam, Germany (PA)
In 2010, German politicians called for plans for the memorial to be abandoned out of respect for the civilian casualties.
Sq Ldr Munro said: “I consider myself a fortunate survivor, ‘Lady Luck’ having sat on my shoulder on several occasions. Yet I think that I left New Zealand on the basic premise that if I was going to cop it, so be it. What will be, will be.
“When fellow officers that I knew relatively well were lost on operations I would feel a brief period of sadness but that had to be quickly relegated to the background of my thoughts.
“There was a job to do and the loss of a colleague could not be allowed to influence how I carried out that job. My duty was to carry out the next operation without emotional distraction. Grief could not be allowed to distract from duty.”
Sq Ldr Munro’s medals are being sold in London on March 25.
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